const fs = require('fs')
const path = require('path')
const sha1 = require('sha1')

const express = require('express')
const router = express.Router()

const UserModel = require('../modles/users')
const checkNotLogin = require('../middlewares/check').checkNotLogin

// GET /signup 注册页
router.get('/', checkNotLogin, function (req, res, next) {
    res.render('signup')
})

// POST /signup 用户注册
router.post('/', checkNotLogin, function (req, res, next) {
    const name = req.fields.name
    const gender = req.fields.gender
    const bio = req.fields.bio
    const avatar = req.files.avatar.path.split(path.sep).pop()
    let password = req.fields.password
    const repassword = req.fields.repassword

    // 校验参数
    try {
    if (!(name.length >= 1 && name.length <= 10)) {
        throw new Error('名字请限制在 1-10 个字符')
    }
    if (['m', 'f', 'x'].indexOf(gender) === -1) {
        throw new Error('性别只能是 m、f 或 x')
    }
    if (!(bio.length >= 1 && bio.length <= 30)) {
        throw new Error('个人简介请限制在 1-30 个字符')
    }
    if (!req.files.avatar.name) {
        throw new Error('缺少头像')
    }
    if (password.length < 6) {
        throw new Error('密码至少 6 个字符')
    }
    if (password !== repassword) {
        throw new Error('两次输入密码不一致')
    }
    } catch (e) {
    // 注册失败，异步删除上传的头像
        fs.unlink(req.files.avatar.path)
        req.flash('error', e.message)
        return res.redirect('/signup')
    }

    // 明文密码加密
    password = sha1(password)

    // 待写入数据库的用户信息
    let user = {
    name: name,
        password: password,
        gender: gender,
        bio: bio,
        avatar: avatar
    }
    // 用户信息写入数据库
    UserModel.create(user)
    .then(function (result) {
        // 此 user 是插入 mongodb 后的值，包含 _id
        user = result.ops[0]
        // 删除密码这种敏感信息，将用户信息存入 session
        delete user.password
        req.session.user = user
        // 写入 flash
        req.flash('success', '注册成功')
        // 跳转到首页
        res.redirect('/posts')
    })
    .catch(function (e) {
        // 注册失败，异步删除上传的头像
        fs.unlink(req.files.avatar.path)
        // 用户名被占用则跳回注册页，而不是错误页
        if (e.message.match('duplicate key')) {
        req.flash('error', '用户名已被占用')
        return res.redirect('/signup')
        }
        next(e)
    })
})

module.exports = router